This invention relates to a fuel control apparatus for use with multi-cylinder internal combustion engines and, more paticular, to a fuel control apparatus of the sequential fuel injection type operating a plurality of fuel injectors in a predetermined sequence.
Sequential fuel injection techniques have been used to inject fuel into a plurality of engine cylinders in a predetermined sequence. Such sequential fuel injection techniques provide significant advantages in that the injected fuel is in a finely atomized form so as to minimize combustion efficiency variations for the respective cylinders and minimize output torque variations.
It is the current practice to start fuel injection for one cylinder at a predetermined engine crankshaft position so as to terminate the fuel injection in the intake stroke of the corresponding piston. With such fuel injection control, however, the time at which the fuel injection is terminated varies with variations in engine speed. For this reason, the fuel injection is terminated sometimes after the termination of the intake stroke, causing poor combustion efficiency.